Shot load



June 1 c. o. WILLIAMS ETAL 3,092,026

sHoT LOAD Filed Sept. 18, 1962 5 sheets-shat 1 INVENTORS CHARLES o.WILLIAMS 2 Z BY CHARLES E TURNER June 4, 1963 c. o. WILLIAMS ETAL3,092,026

SHOT LOAD Filed Sept. 18, 1962 3 Sheets-Sheet 2 INVENTORS CHARLES 0.WILLIAMS CHARLES E TURNER A TIORNEY June 1963 c. o. WILLIAMS ETAL3,092,026

snow LOAD Filed Sept. 18, 1962 5 Sheets-Sheet 5 FIG-5 INVENTORS CHARLES0. WILLIAMS BY CHARLES F. TURNER A 7' TORNEV United States Patent3,092,026 SHOT LOAD Charles 0. Williams, Hamden, and Charles F. Turner,Mount Carmel, Comm, assignors to Olin Mathieson Chemical Corporation, acorporation of Virginia Filed Sept. 18, 1962, Ser. No. 224,378 8 Claims.(Cl. IMP-42) This invention relates generally to ammunition and moreparticularly to an improved shotshell especially of a type containingbuckshot.

.Shotshells containing large sized shot known to the trade as buckshotare provided for killing fairly large game and for use by peace officersin riot guns. Large shot such as No. 2 shot (0.15 of an inch indiameter), BB and buck ranges in size from a diameter of about 0.15 ofan inch up to about 0.33 of an inch or greater and, consequently, only arelatively small number of these relatively large pellets can be loadedand are available in the conventional shotshell cartridge. In order forthese shells to be effective, it is necessary that each of the pelletsmaking up the load follow an even more accurate flight to the targetthan a shell with more but smaller pellets. In other words before suchshells can be extended for certain uses, it is essential that thepellets remain exceptionally close together until they strike thetarget. Shotshell loads heretofore available especially with large sizedshot have not been too satisfactory because the pellets of each loadbecome too widely separated in flight.

It is, therefore, an object of this invention to provide an improvedshotshell containing an exceptionally effective load of shot. Anotherobject of the invention is to provide a shotshell containing aprojectile charge including a few large size shot but neverthelesshaving improved accuracy characteristics. A further object of theinvention is to provide a shot cartridge and especially a buckshotcartridge having shot pellets in combination with auxiliary chargeelements which, when fired, will serve to propel'only the few shot veryaccurately towards the target and which elements offer no interferenceto either the shot or the shooter so an effective number of the pelletswill strike the tar-get unaccompanied by confetti or the like whichmight discomfort or distract the shooter.

Other objects will become apparent from the following description takenin connection with the accompanying drawing in which FIGURE 1 is anelevational and fully longitudinal sectional view of one embodiment ofthe shell of this invention;

FIGURE 2 is an elevational view partly in section showing anotherembodiment similar to that of FIG URE 1 but modified as shown in thesectional part;

FIGURE 3 is a transverse cross sectional view taken along line 3--3 ofeither FIGURE 1 or FIGURE 2;

FIGURE 4 is an enlarged view showing a typical string of twelve N0. 00shot pellets after projection out of the gun barrel from a 12 gauge shotshell of this invention and taken by flash photography at a distance ofabout 12 feet from the gun muzzle; and

:FIGURE 5 for comparison shows a similar View of a typical string of thesame number of No. 00- shot projected from a conventional 12 gaugeshell.

In accordance with this invention, the foregoing objects areaccomplished, generally speaking, by providing a shot load arranged as acolumn having a projectile charge of spherical metal pellets and asuitable shot column encircling sleeve of cushioning material togetherwith a matrix of cushioning material filling the interstices between thepellets in the cartridge.

It has been found that, despite the large size of shot,

a high improvement both in target striking efiectiveness and indurability of the shell case results from a combination of such asleeve, of a special composition, intervening in the case between thecase and shot column, together with the cushioning matrix in the form ofa powder, particularly as the size of shot increases in and with respectto the range from about 0.15 of an inch to about 0.33 of an inch.

The sleeve is an axially or otherwise longitudinally slit layer forminga pad about the column of shot, usually of soft lead, a hardened alloyof lead or of lead plated as with an alloy of copper or with copper toincrease the hardness and durability of the shot. The sleeve is of acushioning material capable of plastic deformation for absorbing theouter shot pellets partially and preferably capable of self lubrication,such as polyethylene. This layer is of such thickness and softnessrelative to both the tubular part of the cartridge case, and also theshot that most of the permanent indentation and scufling and abradingoccurring during shell firing is taken up in the sleeve aided by thecoaction of the powdered cushioning material sifted among the sphericalmetal pellets to form a matrix which distributes the shock of firingmore uniformly, thereby minimizing the creation of high pressure points.

Cartridges having a gauge not smaller than about a 20 gauge shotgunshell and not larger than about a 10 gauge shell are contemplated, but a12 gauge shell is usually preferred as most adaptable to charging withall of the shot sizes involved.

The cushioning material sifted between the spheres is in granular formand may be of any suitable material softer than the spheres. Examples ofsuch cushioning materials include resinous material, either synthetic ornatural, which has the required lightness and rigidity and which can beloaded to a suitable packing density, including cellulose derivativessuch as, for example, cellulose acetate, cellulose propionate, cellulosebutyrate or ethyl cellulose and the like, or acrylic resins,polystyrene, polyvinyl acetate, polyamides, rigid urethanes, and therigid high density grades of polyethylene or the like, or a suitablecellular material such as, for example, ground wheat grains, corn meal,sawdust or the like. The granulation of the cushioning material must besuch that it will fill the interstices between the shot substantiallywithout leaving these interstices as voids. The cushioning material orfiller is either sifted or packed in the interstices in any suitableform so that the particles remain distinct instead of formin a solidfragmentation-resistant slug such as would be obtained by mixing andmolding a cohesive matrix about the shot. A frangible matrix, formingcushioning particles under the impact of firings will also be suitable.

The encircling cushioning and lubricating layer extends over the shotcolumn length in a single thickness of strip which is preferablypress-fitted when loaded in the shot shell case to assume the form of aC-shaped band and thereby preferably prestressed to impart a bias givingthe band a tendency to uncurl, to open out of its substantially closedring shape as soon as it is free of the constraint of the shotgun bore.The band is a layer, plastically deformable by shot indentation andformed from a strip of suitable synthetic plastic material of asufficient length, thickness and pliancy for the purpose.

A layer of high pressure relatively soft, self-lubricating polyethyleneor other similar olefinic polymer for the purpose is contemplated in theform of a band curled to a split-ring shape when constrained incombination with a shot shell case, especially of the type having anevanescent end closure and a self-sealing flanged wad as disclosed inUnited States Patent No. 2,5 82,125 and pref- 3 erably as disclosed inUnited States Patent No. 2,582,124.

A suitably soft grade of polyethylene or any equivalent deformable andunctuous, i.e. waxy, olefinic polymer or co-polymer is contemplated in athickness of not less than about 0.010 of an inch, but not more thanabout the thickness of the thickest shell side Wall encountered, i.e.,not more than about 0.030 to 0.040 of an inch. This forms a plasticallyindentable pad movable as a unit with the short and matrix powder; and,therefore, with the shot and granular matrix, the pad forms part of theprojectile load until ejection from the shotgun muzzle. During passageof the projectile load, the outer shot becomes absorbed partially in thepad by not only plastically indenting the surrounding layer but also byextruding parts of it up between them as the acceleration is applied tothe load in the bore. Exteriorly of the barrel, the powder, and thecollar become free of each other, and fall behind to leave the shot freefrom them.

The plastic takes the form of a suitable length of a rectangular stripbent round and with its extremities in abutment in order to fit snuglywithin the standard cartridge cavity as a seamed collar, but havingsuflicient memory characteristics so as to tend gently to uncoil freefrom the shot column upon emergence from the muzzle. The extremitiesmust not be joined. The length is not more than that of the shot columnso as not to interfere with contiguity of the shot and the end closure.

Other suitable resinous materials are compounds of polyvinyl chloride,ethyl cellulose, cellulose acetate, polyethylene terephthalate and thelike, preferably lubricated and if of a suitable grade for the purpose.At the aforenoted thickness, a collar of solid high pressurepolyethylene of relatively low molecular weight having a Shore durometerhardness of from about 50 to about 75 and preferably around and not inexcess of about 65, measured on the C scale, is contemplated to offerthe necessary degree of deformability, lubricity, and curl-back withouthaving undesired resilience.

The cartridge shown in FIGURE 1 represents a 12 gauge buckshot loadhaving about 12 pellets of shot 2 about 0.33 inch in diameter. This sizepellet is known to the trade as buckshot. The total weight of thepellets is about 488 grains. The pellets were cast from either soft leador a lead-antimony alloy. The shot may be of any other large sizeavailable and the number of pellets enclosed may be varied accordingly.For example, 16 pellets of #1 buckshot having a pellet diameter of about0.3 of an inch or 27 pellets of #4 buckshot having a pellet size of 0.25of an inch may be used. The pellets 2 are enclosed in cartridge case 1of paper (a suitable plastic such as linear high density polyethylene isalso contemplated) and the spaces between the pellets are filled bysifting with a cushioning material 3 such as granular ethyl cellulose.

The granular shot matrix and shot are encircled in the sleeve 40 partedon one side. The cartridge also includes a filler wad 5, a propellantpowder charge 6, a base wad 7, a primer 8, and a metal head 9 around theclosed end or base of the case.

According to above noted US. Patent 2,582,124, the end closure 10 of theFIGURE 1 cartridge is formed of contiguous circular sectors betweenreentrant folded or pie-cut crimps 11, all integral with the case 1folded in all around the shell at 12 to form an evanescent closure incombination with the flanged Wed 14.

The cartridge of FIGURE 2 has case 21 with a metal head 29, shot 22, thematrix of granular cushioning material 23, the cushioning shot sleeve 50and is modified according to US. Patent 2,582,125 so that the flangedwad (not shown because it is like that of FIGURE 1) is combined with theclosed end 30 formed by the rolledover tube portion 31 and the top wad32.

FIGURE 3 shows how the case 21, the shot 22, the matrix 23, and sleeve50, and slit 51 forming a parting on a side, are related in the variousembodiments described and contemplated.

For best results the granules of cushioning material should not be toocoarse, preferably a powder not larger than about 0.050 of an inch isemployed as a filler about the large shot in the split plastic sleeve.In the specific examples described, a fine particulate filler of ethylcellulose, the bulk of which was of a size at least about 0.010 of aninch, having been retained on a 100 mesh screen was sifted between theshot. In any event, the particles must be shaped to be mobile enough toflow readily so as to sift into place between the metal spheres withoutneed for more than pouring and vibration, or moderate tamping and forcefeeding, if packing is employed to increase the amount of matrix powderbetween the shot pellets.

In a 12 gauge shell having 12 pellets of #00 buckshot, the granularethyl cellulose was sifted in to a charge weight of about 25 grains. Ina 12 gauge shell having 27 pellets of #4 buckshot, about 18.3 grainswere sifted in.

The wads may be formed from paper or any other suitable material. Aconventional rolled enclosure may be used with advantage; but withrolled portion 31, end wad 32 is preferably made frangible according toPatent No. 2,582,125 and treated with a water proofing material. Tubes 1and 21 may be a convolutely wound paper tube, a plastic tube or a metaltube. If the plastic resin or metal forms the case, a base wad may notbe required and the separate head 9 or 29 is optional.

The shot pellets, although large are of subcaliber size, i.e., one isnot enough to extend across the cartridge case cavity. They may be ofany suitable metal, including iron, but are usually of lead, or a leadalloy such as one containing a small amount of antimony.

Shot fired from cartridges of this invention are deformed less in theshell case and gun barrel and are more closely spaced when they strikethe target than are shot from prior art cartridges.

As an example, '12 gauge cartridges, some containing 12 pellets of No.00 buckshot, some containing 27 pellets of No. 4 buckshot, and somecontaining 130 pellets of No. 2 chilled shot (1 /2 ounches), all havinga fine ethyl cellulose plastic powder sifted between the shot within asleeve of relatively soft high pressure type of polyethylene, were each,on the average, found to produce a superior pattern in a 30 inch testcircle spaced 40 yards from the muzzle of a shotgun having a full choke,as compared to similar shells lacking either or both of a shotencircling polyethylene collar, and the ethyl cellulose powder.

For example, in the shell of FIGURE 1, the improved No. 00 buckshot loadproduced average patterns of about 100%; the No. 4 buckshot attainedabout 96% on the average, and the No. 2 chilled shot raised the averagepattern from about 77% to about 92%. A pattern of or better isattainable with the shot sizes contemplated.

In comparing the fairly round shot 60 of FIGURE 4 with the string ofshot 70 of FIGURE 5 it should be observed that the shot travels frombottom to top in that direction with reference to the page, and thatwith the (load of this invention (FIGURE 4) there is marked reduction inprojected shot pellet deformation, manifested in conventional shot(FIGURE 5) as the badly flattened areas 71, and that there is reductionof lateral spread in the improved projected shot of FIGURE 4 to giveevidently a tighter pattern or higher pellet density on the target. As aresult, there is attainable an improvement from the 64% to 80% patterndensity now available in conventional loads of this type on the averageup to as high as now available in the loads made according to thisinvention, all as observed at a range of 40 yards in the 30 inchdiameter circle used to test shot patterns.

What is claimed is:

1. A shot cartridge comprising a case having a caliber of from about a20 gauge shotshell to about a gauge shotshell and having a tubular shellwall defining a cavity, a primed cartridge head closing one end of saidcase, a propellant charge in said cavity adjacent said primer, and aclosure mounted at the opposite end of said case and yieldable uponignition of said charge, a projectile load of relatively large andsubstantially spherical shot, all of a diameter smaller than saidcaliber, said shot being arranged in a column in said cavity adjacentsaid closure for forcing said closure open and projection from said caseand through the bore of a shotgun of said gauge in columnar arrangement,a charge obturating means including at least one wad snugly fitted withsaid case in said cavity between said charge and load, a band ofresinous plastic cushioning material softer than said shot extendingbetween said obturating means and yieldable closure and disposed betweensaid column and shell wall to be constrained by said wall to curl said=band about said column in the form of a sleeve open at least at one endadjacent said closure and with a slit down the side, said slitted sleeveproducing its own bias tending to uncurl said band tree from said shotupon emergence from said shotgun bore, and a matrix of relatively fineparticles of non-metallic cushioning material substantially completelyfilling the portion of the sleeve not occupied by the shot, whereby theload is adapted to be projected from said bore free from said sleeve andparticles toward a target with a pattern improved in comparison with thepattern obtainable in the absence of one of said particles and sleeve.

2. The cartridge of claim 1 wherein the load is buckshot and wherein allof the particles are mobile and have no dimension larger than about0.050 of an inch.

3. A shot cartridge comprising a cantridge case, having a caliber offrom about a 20 gauge shotshell to about a 10 gauge shotshell and atubular shell wall defining a cavity, said case being provided at oneend of said wall with a cartridge head carrying 'a primer, a propellentcharge in said cavity adjacent said primer for charge ignition, saidcase being provided at the opposite end of said case with a cavityclosure yieldable upon ignition of said charge, a projectile load ofrelatively large and substantially spherical shot all of about the samesize smaller than said caliber and of a diameter within the range fromabout 0.15 of an inch to about 0.33 of an inch, said shot being arrangedin a column in said cavity adjacent said closure for forcing saidclosure open and projection from said case and through the bore of ashotgun of said gauge in columnar arrangement, a charge obturating meansconsisting of at least one wad snugly fitted with said case in saidcavity between said charge and load, a band of resinous plasticcushioning material softer than said shot extending between saidobturating means and yieldable closure and disposed between said columnand shell Wall to be constrained by said wall to curl about said columnin the form of a sleeve open ended at least at said closure and with alongitudinal slit, said slitted sleeve producing its own bias tending touncurl said band free from said ShOzt upon emergence from said shotgunbore, and a matrix of relatively fine particles of nonmetalliccushioning material substantially completely filling that portion of thesleeve not occupied by the shot, whereby the load is adapted to beprojected from said bore free from said sleeve and particles toward atarget with a high pattern density of at least 4. The cartridge of claim3 wherein the band of resinous plastic cushioning material is apolyethylene.

5. The cartridge of claim 3 wherein the closure is a portion integralwith the tubular shell wall folded across the opposite end of the case,the band upon projection being also constrained by the yielding closure,and the obtur-ating means includes a flanged wad next to the propellantcharge.

6. The cartridge of claim 3 wherein the band of resinous plasticcushioning material is a polyolefin.

7. The cartridge of claim 3 wherein the particles are ethyl cellulose.

8. The cartridge of claim 3 wherein the particles are polyethylene of arigid high density grade.

References Cited in the file of this patent UNITED STATES PATENTS 17,287Lindner May 12, 1857 2,582,125 Holmes Jan. 8, 1952 2,897,758 Miller etal Aug. 4, 1959 FOREIGN PATENTS 6,184 Germany Jan. 19, 1879 416,520Germany July 16, 1925 507,888 France July 8, 1920

1. A SHOT CARTRIDGE COMPRISING A CASE HAVING A CALIBER OF FROM ABOUT A20 GAUGE SHOTSHELL TO ABOUT A 10 GAUGE SHOTSHELL AND HAVING A TUBULARSHELL WALL DEFINING A CAVITY, A PRIMED CARTRIDGE HEAD CLOSING ONE END OFSAID CASE, A PROPELLANT CHARGE IN SAID CAVITY ADJACENT SAID PRIMER, ANDA CLOSURE MOUNTED AT THE OPPOSITE END OF SAID CASE AND YIELDABLE UPONIGNITION OF SAID CHARGE, A PROJECTILE LOAD OF RELATIVELY LARGE ANDSUBSTANTIALLY SPHERICAL SHOT, ALL OF A DIAMETER SMALLER THAN SAIDCALIBER, SAID SHOT BEING ARRANGED IN A COLUMN IN SAID CAVITY ADJACENTSAID CLOSURE FOR FORCING SAID CLOSURE OPEN AND PROJECTION FROM SAID CASEAND THROUGH THE BORE OF A SHOTGUN OF SAID GAUGE IN COLUMNAR ARRANGEMENT,A CHARGE OBTURATING MEANS INCLUDING AT LEAST ONE WAD SNUGLY FITTED WITHSAID CASE IN SAID CAVITY BETWEEN SAID CHARGE AND LOAD, A BAND OFRESINOUS PLASTIC CUSHIONING MATERIAL SOFTER THAN SAID SHOT EXTENDINGBETWEEN SAID OBTURATING MEANS AND YIELDING CLOSURE AND DISPOSED BETWEENSAID COLUMN AND SHELL WALL TO BE CONSTRAINED BY SAID WALL TO CURL SAIDBAND ABOUT SAID COLUMN IN THE FORM OF A SLEEVE OPEN AT LEAST AT ONE ENDADJACENT SAID CLOSURE AND WITH A SLIT DOWN THE SIDE, SAID SLITTED SLEEVEPRODUCING ITS OWN BIAS TENDING TO UNCURL SAID BAND FREE FROM SAID SHOTUPON EMERGENCE FROM SAID SHOTGUN BORE, AND MATRIX OF RELATIVELY FINEPARTICLES OF NON-METALLIC CUSHIONING MATERIAL SUBSTANTIALLY COMPLETELYFILLING THE PORTION OF THE SLEEVE NOT OCCUPIED BY THE SHOT, WHEREBY THELOAD IS ADAPTED TO BE PROJECTED FROM SAID BORE FREE FROM SAID SLEEVE ANDPARTICLES TOWARD A TARGET WITH A PATTERN IMPROVED IN COMPARISON WITH THEPATTERN OBTAINABLE IN THE ABSENCE OF ONE OF SAID PARTICLES AND SLEEVE.